The upset of Sanford, a member of the conservative House Freedom Caucus, was the latest sign of Trump's firm grip on the Republican Party.
But partial returns showed Rep. Mark Sanford, a vocal Trump critic, in a battle with a devout Trump supporter for the nomination in a coastal congressional district.
Smith has served in the state Legislature for 22 years.
A second incumbent Republican congressman has lost his seat in a primary featuring intense divisions among the GOP in the Trump era.
He will face Democratic Sen.
Female candidates: By now, a trend is firmly established. Tim Kaine (D-Va.) race doesn't appear on our list of top-10 most competitive Senate races, but Senate Republicans were hoping to make it competitive by nominating the right candidate to take him on. One ad said "it's time for Mark Sanford to take a hike - for real this time". "He is better off in Argentina", the president wrote. Congrats to Katie Arrington!
Trump had weighed in on the contest via Twitter the previous day while on his way back from Singapore. Keep in mind that Arrington didn't just need to outpoll Sanford.
President Trump's reference to Argentina was a dig at Sanford's 2009 affair scandal during the time he was governor of SC, when he disappeared for several days on a secret trip to Buenos Aires to visit his mistress.
"Mark Sanford has been very unhelpful to me in my campaign to MAGA".
Trump's post was made less than three hours before polls closed.
Yes, that reference to Argentina is the thrice-wedded president (who may have had an affair with a porn star) accusing Sanford of being bad at marriage, apparently without a hint of irony.More news: Police officer rescues young boy running on busy highway
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'She is tough on crime and will continue our fight to lower taxes.
Sanford was critical of Trump during the 2016 presidential campaign, and has found himself on opposite sides with the president since.
"I think it's entirely appropriate to say "I agree" when I agree and "I disagree" when I disagree", Sanford told Politico's Alex Isenstadt. "We have had it with career politicians". "I strongly endorse Adam Laxalt for Governor of Nevada", he tweeted.
The district, which includes Charleston and the southern coast, has not elected a Democrat since 1978.
And in the 3rd District, philanthropist Susie Lee won the Democratic primary, CNN projects, while Republicans could choose Danny Tarkanian, the son of the legendary UNLV basketball coach Jerry Tarkanian, who dropped his Senate bid at the urging of Trump.
With 8 percent reporting according to the Associated Press, McMaster has 44 percent of the vote, but would still face a runoff against John Warren, who has 27 percent.
And in suburban Richmond's Seventh District, former Central Intelligence Agency officer Abigail Spanberger was declared the victor for the Democratic nomination, setting the stage for a fall campaign against GOP Representative David Brat.
Sanford apologized, though the episode ended with his wife divorcing him.
Stewart, who fended off two GOP rivals for the nomination, is a member of the Prince William County Board of Supervisors. On his website he vows to "defeat political correctness, protect Virginia's history, crack down on illegal immigration, and stand up to the Washington elites".
The Senate landscape will become more settled Tuesday night as well.
As expected, North Dakota Republicans chose Rep. Kevin Cramer to challenge Democratic Sen. Heidi Heitkamp, at the 2018 North Dakota Republican Party Convention in Grand Forks, North Dakota, April 7, 2018.